Recently, an increasing number of wind power generators, etc. are being introduced year by year, having a considerable influence on existing power grids. Thus, mainly in Europe and the United States, technical requirements for cooperating with power grids are being specified, and wind power generators (wind farms) are expected to be capable of controlling active power and reactive power so as to contribute to the stabilization of power grids.
Patent Literature 1 discloses a technology in which the range of adjustment of reactive power is increased by adjusting the reactive power using a combination of an electric generator, a power-grid-side power converter attached to the electric generator, other phase modifying equipment, etc.